The Structure of Hematite Pigment from Lathe Waste Using Guava Leave Extract by Hydrothermal Method

Abstract Lathe waste contains 97% iron, which has the potential as a raw material for producing hematite pigment (α-Fe 2 O 3 ). Guava leaf extract contains tannin, a reducing agent in synthesizing hematite. In this study, hematite was synthesized using the hydrothermal method at temperatures of 120, 140, and 160°C, then calcined for 3 hours at a temperature of 750°C. XRD, Color reader, FTIR, and SEM characterized the resulting products. The XRD characterization shows that the product before and after calcination was hematite with a rhombohedral structure. Hematite before calcination resulted in an amorphous phase and formed high crystallinity and purity after calcination. The crystal size of hematite ranges from 24.8-34.2 nm. The Color values such as the degree of redness, yellowness, brightness, chroma, and hue are by the hematite pigment standard. The results of FTIR identification on samples before and after calcination have formed hematite with a typical Fe-O group at wave numbers 471 and 575 cm −1 . SEM results show that the resulting morphology was not uniform, and aggregate occurs, the necessity for further research to optimize the material’s properties, thereby improving its functionality for applications as a pigment and in other relevant fields.